Adjustable shore



A. HAHN Dec. 22, 1959 ADJUSTABLE snow:

Filed March 4, 1955 5 :1 Z T 2 w W i A m F mNNN F 3 Dec. 22, 1959 A.HAHN ADJUSTABLE SHORE 5 Sheets-Sheet 2 Filed March 4. 1955 INVENTORAmwma Hahn Dec. 22, 1959 A. HAHN 2,918,257

ADJUSTABLE SHORE Filed March 4, 1955 3 Sheets-Sheet 5 K 3 V y i W IINVENTOR (Jammkv Hahn WMw1 s. a tA gw United States Patent ADJUSTABLESHORE Alexander Hahn, Laguna Beach, Calif.

Application March 4, 1955, Serial No. 492,289 Claims priority,application Germany May 15, 1952 Claims. (Cl. 254105) The presentinvention relates to an adjustable shore and more particularly to anadjustable shore which can be extended under load.

This application is a continuation-in-part of copending applicationSerial No. 354,807, filed on May 13, 1953, now abandoned, and entitledAdjustable Shores for Planking, Framing and the Like.

One object of the present invention is to provide a shore which can behandled very easily and which can be adjusted under load in a veryconvenient manner.

A further object of the present invention is to secure the two parts ofthe shore in an extended position automatically and in a very reliableand safe manner.

An additional object of the invention is to make the stripping of theshore, if the same is to be removed, possible without damaging theshore.

Another object of the invention is to provide a shore which is veryrugged in its construction and which can be manufactured at a relativelylow cost.

With the above objects in view, the present invention mainly consists inan adjustable shore, the length of which can be adjusted under load,comprising the following elements; an outer strut, an inner strut atleast partly surrounded by the outer strut, lifting means mounted on oneof these struts for lifting the other of these struts from a startingposition to a final position, and holding means carried by one of thesestruts and engag ing the other strut to prevent the latter from movingdown, after being lifted by the lifting means, through the distance ithas been lifted by the lifting means.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, to gether with additional objects and advantages thereof,will be best understood from the following description of specificembodiments when read in connection with the accompanying drawings, inwhich:

Fig. 1 is a partial sectioned front view of part of the shoreconstruction;

Fig. 1a is a partial sectioned front view of part of a modified form ofthe shore construction;

Fig. 2 is a top view of the shore construction;

Fig. 3 is a sectional side view of a part of the shore construction;

Fig. 4 is a schematic front view of the whole shore construction; 1

Fig. 5 is a partial sectioned front view of a modified shoreconstruction;

Fig. 6 is a partial sectioned front view of another modification of thisconstruction showing the elements in engaged position; and

Fig. 7 is a top view of this modification showing the elements indisengaged position.

Referring now to the figures, and more particularly to Fig. 4, theadjustable shore consists of an outer strut 1, an inner strut 2surrounded by said outer strut and slidably arranged in the same, sothat the total length 2, of the shore can be extended or shortenedaccording to requirements. Both struts are preferably made from roundsteel tubes, but of course the invention is not limited to the preferredform of these struts and they may have any other cross section, such assquare, oval or polygonal. Instead of a tube, a solid rod or bar mayalso be used for the inner strut. End plates 15 and 15' are respectivelyarranged at the extreme outer ends of the inner and the outer strut, andthese plates are preferably hingedly connected to the respective strutmembers.

The strut is further provided, as illustrated in detail in Fig. 1, witha lifting mechanism and a locking mechanism, to be able to adjust theoverall length of the shore by lifting the inner strut out of the outerstrut from a starting position to a final position and to secure theT6131 tive position of the two strut members in its final positionautomatically. The lifting mechanism consists in a disc 6 turnablymounted on pin 7 which pin is eccentrically arranged on said disc sothat when the disc is turned the peripheral face of the disc is movedtoward or away from the outer surface of the inner strut 2, depending onthe direction the disc is turned. The eccentricity e of the pin axiswith relation to the disc axis, the position of this pin 7 and thediameter of the disc 6 is chosen in such a way that when the disc ismoved in a clockwise direction as viewed in Fig. 1, the peripheralsurface of the disc will engage the inner strut member 2 with increasingpressure. Part of this peripheral surface is provided with grippingteeth 10 which dig into the outer surface of the strut 2 when the disc 6is turned in clockwise direction and lift upon further turning of thedisc the strut 2 outwardly of strut 1. The journal pin 7 is preferablyslidably mounted in elongated slots 8 inclined downwardly and inwardlytowards the strut axis so that these slots include an angle of 1525 withthe longitudinal axis of the struts. The turning of the disc 7 isstarted with the pin 7 at the bottom of these slots. After the teeth 10have gripped the inner strut the pin 7 will, upon further turning of thedisc, slide upwardly in these slots, as the distance between successivecontacting points of the disc and the center point of the pin increasesdue to the eccentric mounting of the disc on the pin. The slots 8 areprovided in two parallel bearing brackets 4 which in turn are fixedlyconnected, preferably by welding, to a sleeve 3 surrounding the upperend portion of the outer strut 1 and rigidly attached to the same, bywelding or any other manner. The two brackets 4 can, if desired, also bewelded directly to the outer strut '1, but the construction shown,having a separate sleeve 3 surrounding the upper end of strut 1, ispreferred as being much stronger. The sleeve 3 and the upper portion ofstrut 1 surrounded by this sleeve are provided with a slot 9 between thetwo bearing brackets 4 so that the aforementioned disc 6 may reachthrough this slot to contact the inner strut member. A handle 5 isfixedly connected, preferably Welded, to the disc 6, so that the disccan be turned easily.

Instead of the round disc a lever 6 being journaled on a pin 7, havingon one side a contacting face similar to that of the disc and extendingon the other side into a handle, can also be used. Instead of closedslots 8, upwardly extendingfaces 8 inclined in the same direction asthose slots, may be provided at the upper portion of the brackets 4". Inthis case the pin 7' will abut against these faces during the turning ofthe lever and the latter may be removed from the bracket when not inuse. Such a modification is shown in Fig. 1a.

The bearing brackets 4 carry besides the aforementioned lifting members6a locking lever 17 which is turnably mounted on a pin 16 journaled inthe brackets 4. This lever projects likewise through the slot 9 and hasan end face contacting the outer surface of the inner strut member 2.This end face is provided with gripping teeth 18 and the position of thepin 16, and the distance between pin and end face is arranged in such away that the lever 17 is always held in a slightly upwardly extendingposition.

When the inner strut 2 is lifted by turning the disc 6 in a clockwisedirection, as viewed in Fig. 1, the lever 17, contacting the inner strutwith its end face, is also slightly tilted in the same direction. Assoon as the handle is released and the inner strut slides slightlydownwardly, the lever 17 contacting the outer surface of the strut '2 isturned in counterclockwise direction whereby the teeth 18 dig slightlyinto the outer surface of strut 2 and the strut is pressed as thecontacting end of lever 17 moves during the tilting of the lever,further further inwardly, with increasing force against the innersurface of the outer strut opposite lever 17 and the teeth '18 digfurther into the strut 2, so as to lock the two struts together. In theconstruction in Fig. 1, a stop provided at the lower end faces of slot 9stops the turning movement of lever 17 and prevents lever 17 to reach orpass a horizontal position. It should be noted that the holding lever 17acts completely automatically and independent from the lifting mechanism6. A further advantage of the construction described is that theclamping forces resultin from the turning of the lever are distributedover a large area. Instead of a single holding lever 17 a second similarlever could be provided in the same manner but diametrically opposite ofthe shown lever. In this case, of course, similar brackets and a similarslot would have to be provided on the opposite side of the sleeve '3.

If desired, the lifting disc '6 can also be 'used as an additionallocking means to hold the inner strut in its final position. In theconstruction shown in Fig. 1 this is accomplished by providing anarresting or locking mechanism to hold the disc 6 in its final positionat the end of the lifting stroke. For this purpose, the disc is providedwith a plurality of holes '12, evenly spaced along a pitch circleadjacent to the peripheral face of the disc, and perpendicular to itsend faces. The two bearing brackets 4 are likewise provided with aplurality of holes 14 having a slightly smaller diameter than holes 12and being evenly arranged along a pitch circle having the same diameterand center as the aforementioned pitch circle, but the number of theseholes is made smaller by one than the number of holes carried by thedisc, to obtain a Vernier arrangement, in which in practically anyposition of the disc one hole in the disc will be in alignment with apair of holes in the bearing brackets. A pin 13 is then inserted throughthese aligned holes to fix the position of the disc in relation to thebrackets. The disc therefore cannot turn back under the load of theinner strut and the teeth of the disc support the action of the teeth 18of the holding lever. To increase the pressure of the teeth 10 againstthe inner strut 2 further, the bearing brackets 4 are as explainedbefore provided with elongated slots 8. The disc pin 7 which isslidingly arranged in these slots will move from its upper position atthe end of turning stroke downwardly whereby when the disc 6 is held inits arrested position the periphery of the disc 6 and the teeth 10 arepressed with increasing pressure against the outside surface of strut 2,which action supports the action of the locking lever and results in avery secure locking of the strut member.

Fig. 5 shows a different arrangement for arresting the disc 6 in its'final position. Instead of the hole and pin arrangement illustrated inFig. 1, a ratchet arrangement is provided. For this purpose the upperfaces of the brackets 4 are arcuately shaped and locking teeth 22areprovided in this arcuate top portions of the brackets. A pawl 20tiltably mounted on the handle 5 cooperates with the locking teeth 22 toallow a rotation of disc 6 and handle 5 in clockwise direction, asviewed tn Fig. 5,

and to prevent such a rotation in counterclockwise direc- ".75

tion. A spring 21, one end of which is housed in a bore at the end ofthe locking pawl opposite its locking tooth, and the other end of whichis housed in a corresponding bore in the disc in line with the bore inthe pawl, keeps the tooth end of the locking pawl always in engagementwith the teeth '22. As can be clearly seen, the disc 6 can be turned toengage with increasing pressure the inner strut 2 and to lift the sameupwardly, whereas the return stroke which would allow the inner strut toslide downwardly is prevented by this locking arrangement.

Fig 5 illustrates a further improvement over the construction shown inFig. 1. As shown in Fig. 5 a spring 19 is provided. The middle part ofthis spring is wound around a pin held in the bearing brackets, one ofits free ends is projecting into a hole in one of the bearing bracketsto fix the position of the spring, whereas the other free end of thespring presses against the side face of the holding lever 17 so as topush the front face and the teeth 18 provided in this front face of thelever against the outer surface of strut 2. The spring 19, of course,does not provide the necessary pressure for a secure locking betweenlever end face and strut, which is provided, as described above, by theload of the inner strut and the particular dimensioning and positioningof the lever 17, but the spring assures a continuous contact between theend face of the lever 17 and the strut 2 regardless of friction betweenpin 16 and lever 17 or tolerance deviations in the strut 2. Instead oflimiting the tilting movement by the end faces 23, a pin 24- projectingfrom one of the inner end faces of brackets 4 into the path of the lever17 or any other stop between the brackets can also be provided.

The gripping teeth on lever 17 may be cut with the upper face parallelto the longitudinal lever axis as shown in Figs. 1 and 5. To provide formore sturdy teeth and for an easy disengagement of the locking teeth 18from the indentations they make during clamping on the inner strut,these locking teeth have preferably a cross section in the form ofisosceles triangles, the sides of which including an angle of 60 to asshown in Fig. 6. The teeth on lever 17 are cut on a surface having alower curved portion and an upper substantially straight portionsubstantially tangential to the curved portion, so that at the end ofthe turning movement of this lever, teeth on the straight portion maycontact the inner strut and provide for a secure stop. The bearingbracket shown in Figs. 6 and 7 is also slightly different from thebear-- ing bracket previously described. The bearing bracket shown,consists of a preferably cast sleeve 4' securely clamped to the outerstrut 1 by means of a screw 26 pressing the two flanges 27 of the slitcasting 4' together or welded or threaded to the outer strut. The spring19 is also slightly modified and consists of a two-arrn spring, the freeends of which abut against a rear part of the casting, the two coils ofwhich are located around cast bosses 28, projecting inwardly from sidefaces of the sleeve, whereas the middle portion of the spring pressesagainst the side face of the locking lever 17". The constructionillustrated in Figs. 6 and 7 shows further means for an easydisengagement of the locking teeth 18 on the lever 17' from the innerstrut 2. The locking lever 17 is turnably arranged around an eccentricpin 16. This pin has two outer journal portions 29 journaled in thebearing bracket 4' and an eccentric middle portion 3%, whcih carries thelocking lever 17'. A handle 31 is fixedly attached to one of the endportions of this pin protruding beyond the bearing bracket 4' to make aneasy turning of the eccentric pin possible. As can be seen from thedrawings, the front end of the lever 17 can be moved towards and fromtheouter surface of the strut 2 it is contacting, by turning the pin 16' bymeans of the handle 31. The end face of the lever 17' will thereby movein a direction substantially normal to the strut axis and the lockingteeth on the end face and on the strut member can be disengaged in thismanner very easily, and without damaging any of the engaging parts, whensuch a disengagement is desired in order to collapse the extended shore.

Thegripping teeth on the lever 17, 17' and/or on the disc member 6 orthe lever 6' are preferably cut along a contour corresponding to theshape of the surface portion of the inner strut member 2 contacted bythe same so that they engage this strut substantially along their wholesurface and not only along a line.

Instead of constructing the disc 6 or the lever 6' as an eccentric, itsperipheral face in which the teeth are cut may be formed along anevolvent, a hyperbolic or any othercam curve, which will upon turning ofthe disc in one direction create increasing pressure on the inner strut.The teeth on levers 17, 17', respectively, are also cut along similarcurves.

It will be understood that each of the elements described above, or twoor more together, may also find a useful application in other types ofadjustable shores differing from, the types described above. 7

While the invention has been illustrated and described as embodied inadjustable shore, it is not intended to be limited to the details shown,since various modifications and structural changes may be made withoutdeparting in any way from the spirit of the present invention.

What is claimed as new and desired to be secured by Letters Patent is: 1r

1. An adjustable shore the length of which can be adjusted under load,comprising, in combination, a tubular outer strut; an elongated innerstrut having a substantially smooth outer surface and being located atleast partly within said outer strut'for movement therealong; supportmeans carried by said outer strut and having at least one bearingsurface inclined toward the strut axis so as to include an acute anglewith the same; a disc supported on said bearing surface of said supportmeans for sliding movement and for turning movement about an axissubstantially perpendicular to that of said struts and spaced from theaxis of said disc so that a peripheral surface portion of the lattermoves toward an outer surface portion of said inner strut during turningof said disc in one direction on said support means and away from saidouter surface portion upon turning of said disc in opposite direction,said surface portions of said disc and inner strut being in engagementwith each other; means carried by at least one ,of said surface portionsfor reducing the slip between the same to. a minimum; a lever turnablycarried by said support means for movement about an axis substantiallyparallel to the turning axis of said disc and said lever extendingupwardly from its turning axis toward said inner strut and having alength between said strut and said latter turning axis greater than thedistance from said inner strut to said latter turning axis, said innerstrut having a second surface portion engaging an end surface portion ofsaid lever; and means on at least one of said latter two surfaceportions for reducing the slip between said lever and inner strut to aminimum.

2. An adjustable shore the length of which can be adjusted under load,comprising, in combination, a tubular outer strut; an elongated innerstrut having a substantially smooth outer surface and being located atleast partly within said outer strut for movement therealong; supportmeans carried by said outer strut andhaving at least one bearing surfaceinclined toward the strutgaxis so as to include an acute angle with thesame;

a disc supported on said bearing surface of said support means forsliding movement and for, turning movement about an axis substantiallyperpendicular to that of said struts andspaced from the axis of saiddisc, so that a peripheral surface portion of the latter moves toward anouter surface portion of said inner strut during turning of said disc inone direction on said support means and away from said outer surfaceportion upon turning of said disc in opposite direction, saidsurfaceportions ofsaid disc and inner strut being int-engagement ;with eachother; gripping teeth provided on said surface portion-of said disc forgrippingly engaging said outer surface portionof said inner strut; ahandle fixedly attached to saiddisc and extending from the sam e'forfacilitating the turning movement of said disc; a lever turnably carriedby said support means for movement about an axis substantially parallelto the turning axis of said disc and said lever extending upwardly fromits turning axis toward said inner strut and having a length betweensaid strut and said latter turning axis greater than the distance fromsaid inner strut to said latter turning axis, said inner strut having asecond surface portion engaging an end surface portion of said lever;and gripping teeth provided on said endsurface portion of saidlever forgrippingly engaging said second surface portion of said inner strut. 3

3. An adjustable shore the length of which can be adjusted under load,comprising, in combination, a tubular outer strut; an elongated innerstrut having a substantially smooth outer surface and being located atleast partly within said outer strut for movement therealong; bearingbrackets carried by said outer strut, each being provided with anelongated slot having closed ends and converging toward the strut axisso as to include an acute angle with the same; a disc supported in saidslots for a sliding movement and for a turning movement about an axissubstantially perpendicular to that of said struts and spaced from theaxis of said disc so that a peripheral surface portion of the lattermoves toward an outer surface portion of. said inner strut duringturning of said disc in one direction on said support means, and awayfrom said outer surface portion upon turning of said disc in oppositedirection, said surface portions of said disc and inner strut being inengagement with each said disc and extending from the same forfacilitating the,

turning movement of said disc; a lever turnably carried by said bearingbrackets for movement about an axis substantially parallel to theturning axis of said disc and said lever extending upwardly from itsturning axis toward said inner strut and having a length between saidstrut and said latter turning axis greater than the distance from saidinner strut to said latter turning axis, said inner strut having asecond surface portion engaging an end surface portion of said lever;gripping teeth provided on said end surface portion of said lever forgrippingly engaging said second surface portion of said inner strut; anda slot provided in said outer strut between said hearing bracketsthrough which said disc and said lever project toward said inner strutto engage the same.

4. An adjustable shore adjusted under load, comprising, in combination,a tubular outer strut; an elongated inner strut having a substantiallysmooth outer surface and being located at least partly within said outerstrut for movement therealong; bearing brackets carried by said outerstrut, each being provided with an elongated slot having closed ends andconverging toward the strut axis so as to include an acute angle withthe same; a disc supported in said slots for a sliding movement and fora turning movement about an axis substantially perpendicular to that ofsaid struts and spaced from the axis of said disc so portions of saiddisc and inner strut being in engagement witheach outer; gripping teethprovided on said surface portion of said disc for grippingly engagingsaid outer surfaceportion of said inner strut; a handle fixedly attachedto said disc and extending from the same for the length of which can befacilitating the turning movement of said disc; locking means forlocking the turning movement of said disc in at least one direction; alever turnably carried by said bearing brackets for movement about anaxis substantially parallel to the turning axis of said disc and saidlever extending upwardly from its turning axis toward said inner strutand having a length between said strut and said latter turning axisgreater than the distance from said inner strut to said latter turningaxis, said inner strut having a second surface portion engaging an endsurface portion of said lever; gripping teeth provided on said endsurface portion of said lever for grippingly engaging said secondsurface portion of said inner strut; and a slot provided in said outerstrut between said bearing brackets through which said disc and saidlever project toward said inner strut to engage the same.

5. An adjustable shore the length of which can be adjusted under load,comprising, in combination, a tubular outer strut; an elongated innerstrut located at least partly within said outer strut for movementtherealong; bearing brackets carried by said outer strut, each beingprovided with an elongated slot having closed ends and converging towardthe strut axis so as to include an acute angle with the same; a discsupported in said slots for a sliding movement and for a turningmovement about an axis substantially perpendicular to that of saidstruts and spaced from the axis of said disc so that a peripheralsurface portion of the latter moves toward an outer surface portion ofsaid inner strut during turning of said disc in one direction on saidsupport means and away from said outer surface portion upon turning ofsaid disc in opposite direction, said surface portions of said disc andinner strut being in engagement with each other, said disc havingparallel end surfaces formed with a plurality of holes perpendicular tosaid end surfaces and evenly spaced on a pitch circle adjacent to saidperipheral surface, and each of said bearing brackets being providedwith a plurality of holes evenly spaced about a pitch circle having thesame center and diameter as said pitch-circle of said holes on saiddisc, the number of said holes in each of said bearing brackets being byone smaller than the number of said holes in said disc, to provide avernier arrangement for aligning said holes in said disc with said holesin said brackets; a pin for selectively projecting through aligned holesin said disc and said bearing brackets to prevent a turning move ment ofsaid disc; gripping teeth provided on said surface portion of said discfor grippingly engaging said outer surface portion of said inner strut;a handle fixedly attached to said disc and extending from the same forfacilitating the turning movement of said disc; a lever turnably carriedby said bearing brackets for movement about an axis substantiallyparallel to the turning axis of said disc and said lever extendingupwardly from its turning axis toward said inner strut and having alength between said strut and said latter turning axis greater than thedistance from said inner strut to said latter turning axis, said innerstrut having a second surface portion engaging an end surface portion ofsaid lever; gripping teeth provided on said end surface portion of saidlever for grippingly engaging said second surface portion of said innerstrut; and a slot provided in said outer strut between said bearingbrackets through which said disc and said lever project toward saidinner strut to engage the same.

6. An adjustable shore the length of which can be adjusted under load,comprising, in combination, a tubular outer strut; an elongated innerstrut located at least partly within said outer strut for movementtherealong; bearing brackets carried by said outer strut, each beingprovided with an elongated slot having closed ends and converging towardthe strut axis so as to include an acute angle with the same, and eachhaving an arcuate surface provided with locking teeth; a disc supportedin said slots for a sliding movement and for a turning movement about anaxis substantially perpendicular to that of said struts and spaced fromthe axis of said disc so that a peripheral surface portion of the lattermoves toward an outer surface portion of said inner strut during turningof said disc in one direction on said support means and away from saidouter surface portion upon turning of said disc in opposite direction,said surface portions of said disc and inner strut being in engagementwith each other; gripping teeth provided on said surface portion of saiddisc for grippingly engaging said outer surface portion of said innerstrut; a handle fixedly attached to said disc and extending from thesame for facilitating the turning movement of said disc; a locking pawlturnably mounted on said handle having oppositely directed free ends,one of said free ends being provided with a locking tooth engaging saidlocking teeth provided on said arcuate surface; a spring engaging theother free end of said locking pawl for keeping said locking tooth inengagement with said locking teeth on said arcuate surface and to allowturning of said disc only in a direction for lifting said inner strut; alever turnably carried by said bearing brackets for movement about anaxis substantially parallel to the turning axis of said disc and saidlever extending upwardly from its turning axis toward said inner strutand having a length between said strut and said latter turning axisgreater than the distance from said inner strut to said latter turningaxis, said inner strut having a second surface portion engaging an endsurface portion of said lever; gripping teeth provided on said endsurface portion of said lever for grippingly engaging said secondsurface portion of said in-v ner strut; and a slot provided in saidouter strut between said bearing brackets through which said disc andsaid lever project toward said inner strut to engage the same.

7. An adjustable shore the length of which can be adjusted under load,comprising, in combination, a tubular outer strut; an elongated innerstrut located at least partly within said outer strut for movementtherealong; bearing brackets carried by said outer strut, each being providedwith an elongated slot havingclosed ends and converging toward the strutaxis so as to include an acute angle with the same; a disc supported insaid slots for a sliding movement andfor a turning movement about anaxis substantially perpendicular to that of said struts and spaced fromthe axis of said disc so" that a peripheral surface portion of thelatter moves: toward an outer surface portion of said inner strut duringturning of said disc in one direction on said support means and awayfrom said outer surface portion upon turning of said disc in oppositedirection, said surface portions of said disc and inner strut being inengagement with each other; gripping teeth provided on said surfaceportion of said disc for grippingly engaging said outer surface portionof said inner strut; a handle fixedly attached to said disc andextending fromthe same for facilitating the turning movement of saiddisc; a lever turnablycarried by said bearing brackets for movementabout an axis substantially parallel to the turning axis of said discand said lever extending upwardly from its turning axis toward saidinner strut and having a length between said strut and said latterturning axis greater than the distance from said inner strut to saidlatter turning axis, said inner strut having a second surface portionengaging an end surface portion of said lever; gripping teeth providedon said end surface portion of said lever for grippingly engaging saidsecond surface portion of said inner strut; spring means carried by saidbearing brackets and engaging said lever for keeping said gripping teethprovided on said end surface portion of said lever in engagement withsaid inner strut; and a slot provided in said outer strut between saidbearing brackets through which said disc and said lever project towardsaid inner strut to engage e s m i g l j a 8. An adjustable shore thelength of which can be U adjusted under load, comprising, incombination, a tubular outer strut; an elongated inner strut located atleast partly within said outer strut for movement therealong; bearingbrackets carried by said outer strut, each being provided with anelongated slot having closed ends and converging toward the strut axisso as to include an acute angle with the same; a disc supported in saidslots for a sliding movement and for a turning movement about an axissubstantially perpendicular to that of said struts and spaced from theaxis of said disc so that a peripheral surface portion of the lattermoves toward an outer surface portion of said inner strut during turningof said disc in one direction on said support means and away from saidouter surface portion upon turning of said disc in opposite direction,said surface portions of said disc and inner strut being in engagementwith each other; gripping teeth provided on said surface portion of saiddisc for grippingly engaging said outer surface portion of said innerstrut; a handle fixedly attached to said disc and extending from thesame for facilitating the turning movement of said disc; a leverturnably carried by said bearing brackets for movement about an axissubstantially parallel to the turning axis of said disc and said leverextending upwardly from its turning axis toward said inner strut andhaving a length between said strut and said latter turning axis greaterthan the distance from said inner strut to said latter turning axis,said inner strut having a second surface portion engaging an end surfaceportion of said lever; gripping teeth provided on said end surfaceportion of said lever for grippingly engaging said second surfaceportion of said inner strut; spring means carried by said bearingbrackets and engaging said lever for keeping said gripping teethprovided on said end surface portion of said lever in engagement withsaid inner strut; stop means for limiting the turning movement of saidlever and to keep said lever in an upward extending position; and a slotprovided in-said outer strut between said bearing brackets through whichsaid disc and said lever project toward said inner strut to engage thesame.

9. An adjustable shore the length of which can be adjusted under load,comprising, in combination, a tubular outer strut; an elongated innerstrut located at least partly between said outer strut for movementtherealong; bearing brackets carried by said outer strut, each beingprovided with an elongated slot having closed ends and convergingtowards the strut axis so as to include an acute angle with the same; adisc supported in said slots for a sliding movement and for a turningmovement about an axis substantially perpendicular to that of saidstruts'and spaced from the axis of said disc so that a peripheralsurface portion of the latter moves toward an outer surface portion ofsaid inner strut during turning of said disc in one direction and awayfrom said outer surface portion upon turning of said disc in or positedirection, said surface portions of said disc and inner strut being inengagement with each other; gripping teeth provided on said surfaceportion of said disc being in engagement with said surface portion ofsaid inner strut for grippingly engaging the latter; a handle integrallymade with said disc and extending from the same for facilitating theturning movement of said disc; a pin having journal portions carried bysaid bearing brackets for a turning movement about an axis substantially parallel to the turning axis of said disc, and a middle portionintegral with and eccentric to said journal portions; a locking leverturnably carried by said middle portion for movement about an axissubstantialiy parallel to the turning axis of said disc, and said leverextending upwardly from its turning axis toward said inner strut andhaving a length between said strut and said latter turning axis greaterthan the distance from said inner strut to said latter turning axis,said inner strut having a second surface portion engaging an end surfaceportion of said lever; gripping teeth provided on said end surfaceportion of said lever; spring means carried by said bearing brackets andengaging said lever for keeping said gripping teeth on said lever endsurface in engagement with said second surface portion on said innerstrut; a lever fixedly attached to said pin for turning the same and fordisengaging said gripping teeth provided on said end surface portion ofsaid lever from said second surface portion of said inner strut in adirection substantially normal to the strut axis; and a slot provided insaid outer strut between said bearing brackets through which said discand said lever project toward said inner strut to engage the same.

10. An adjustable shore according to claim 9 and the end faces of saidgripping teeth on said disc and said lever formed to correspond to theshape of said portions of the inner strut engaged by the same.

References Cited in the file of this patent UNITED STATES PATENTS538,920 Joyce Oct. 29, 1895 781,147 Joyce Jan. 31, 1905 1,349,576Markham Aug. 17, 1920 1,364,117 Kohorst Jan. 4, 1921 1,372,005 BrandtMar. 22, 1921 1,399,693 Day Dec. 6, 1921 1,499,755 Stebbins July 1, 19242,060,214 Hitchens Nov. 10, 1936 FOREIGN PATENTS 580,046 France Aug. 20,1924 593,189 Germany Feb. 22, 1934

